1. Field of the Invention
This invention relates to a method of forming a binding around at least one article by means of a length of stiff wire, to an apparatus for binding at least one article by such a method and to an article or articles bound by the method. Where a plurality of articles is bound by the method, they are referred to in this description as a bundle of articles. Typically the articles bound are elongate, e.g. are metal rods or strips.
2. Description of the Prior Art
EP-A-74985 describes a method using a piece of stiff wire for forming a binding around a bundle of rod material, in which the piece of wire is led around the bundle once and a join is made between the head and tail of the piece of wire. FIG. 1 of the present drawings illustrates the resultant bound bundle. The apparatus for binding comprises an annular structure provided with a channel for guiding the wire, which channel is U-shaped in cross-section with the open side of the U facing the bundle inserted for binding by the annular structure.
By this method and apparatus the wire is guided once around the bundle to be bound. Then, with its head held fast, the wire is pulled back so that it lies in one tight turn around the bundle, then it is knotted and cut so that a binding with one turn is created.
GB-A-1001385 illustrates a similar method and apparatus in which it is additionally suggested that the guide path for the wire in the annular guide may have more than one turn, so that two or more turns of the wire around the article being bound are made. Again the wire is pulled tight by pulling its ends, before it is knotted.
The bound bundles created by these methods consist of, for example, concrete reinforcing steel rods. In general the bundles subsequently must be transported and stored several times. In practice the bundles are handled by lifting. A problem with this is that the bundles bound in the known manner have no suitable lifting points. It has been found that the known binding cannot serve as lifting point because, when the binding is taut, a lifting hook cannot be hooked around the wire, and even if that is possible with a slightly looser binding the knot does not hold. The result is that many different means of lifting have to be available for handling and storage. Typically, along the handling route of the bundles there are chains and straps which have to be placed around the stored bundles before they can be lifted.